1. Field of the Invention
The present invention relates to a fueling device for fueling a fuel tank through a passage of a fuel filler pipe.
2. Description of the Related Art
In conventional fueling devices for fueling a fuel tank through a filler pipe, the fuel cap is open when fuel is supplied through a fuel filler pipe. The fuel cap has a sealing member which, in a closed position, is inserted between the cap and an inlet opening of the fuel filler pipe to prevent fuel vapor in the fuel tank from escaping into the atmosphere. The sealing member is in the form of a gasket extending around the periphery of a cylindrical casing main body. When the fuel cap is screwed onto the opening of the filling neck, the gasket provides air-tight sealing force, while subject to torque caused by rotating friction force, against the filling neck.
Applicant has found that such torque is not readily applied uniformly across the gasket as a whole, and complicates efforts to improve the sealing properties. Additionally, the gasket is removed with the fuel cap when the fuel cap is placed in the open position, resulting in stains and damage to the seal surface of the gasket. In such cases, not only are the sealing properties of the gasket compromised, but there is greater friction resistance with the gasket, tending to result in greater operating force required to open and close the fuel cap.
Furthermore, when a fueling gun is introduced into the inlet opening, the fueling gun strikes the inlet opening, damaging the seal in the opening in contact with the gasket. The sealing properties are compromised in this case as well due to possible damage to the gasket.
An object of the present invention is to provide a fueling device with better fuel cap operation when removed and returned to an inlet opening, as well as better fuel tank sealing properties for preventing escape of the fuel to the atmosphere.
In accordance with one embodiment of the present invention, a fueling device for fueling a fuel tank through the fuel passage of a fuel filler pipe comprises a casing main body that is disposed in the fuel passage of the fuel filler pipe. The casing main body has an inlet opening for introducing fuel. A cap main body having a handle allows the fuel passage to be opened and closed, and is capable of opening and closing the inlet opening by the operation of the handle. A shutter is coupled to the casing main body and is disposed in the fuel filler pipe for opening and closing the fuel passage. A connector couples the cap main body to the shutter in such a manner that an operating force exerted by the handle to close the fuel passage applies a closing force to the shutter to close the shutter.
The cap main body attached to the inlet opening of the casing main body is detachable from the fuel filler pipe to allow fuel to be supplied through the fuel passage of the fuel filler pipe into the fuel tank. When the cap main body engages the casing main body and is operated in the closing direction in order to close the inlet opening, its force is transmitted via the connector to the shutter. The connector converts force in the direction in which the handle closes the fuel passage into a closing force in the direction in which the shutter closes the fuel passage. This allows the shutter to close the fuel passage and maintain the fuel passage closed with higher sealing properties.
Preferably, the casing main body is detachable from the fuel filler pipe, and can comprise a seal component operable to press against the inner wall of the fuel filler pipe to seal the space therebetween. The casing main body can also comprise a cover detachably supporting the cap main body.
Also, the casing main body can be fixed to the fuel filler pipe while simultaneously sealing the inside of the fuel filler pipe against the outside, so as to improve the sealing and assembly properties.
The casing main body can also comprise a seat with a seat surface in a location facing away from the inlet opening, and a seal component detachable from the seat surface, wherein the handle is operated in the closing direction to allow the shutter to press the seal component against the seat surface. Consequently, the force in the direction in which the shutter closes the passage is transmitted to the seal component, providing even better sealing properties. The seal component may be mounted on the casing main body, the shutter, or the like. If the seat surface faces away from the inlet opening so as to be hidden from the opening in the fuel passage, the fuel gun will not strike the seat surface when the fuel gun is inserted into the fuel passage. The sealing properties are thus not compromised by damage to the seat surface.
The shutter preferably comprises a biasing member urging the seal component against the seat surface so as to enhance the sealing force in conjunction with the force applied when handle closes the passage. The biasing member urges the shutter towards the seat surface to main the fuel passage closed by the shutter until the shutter is pressed open by the fuel gun, which applies a force sufficient to overcome the biasing force.
The seat surface is also disposed on the inside of the fuel filler pipe in the present invention, and the seat surface is sealed by the seal component pressed by the shutter. Accordingly, rather than sealing the spirally expanding opening of the fuel filler pipe as in conventional techniques, the seal component can be made smaller, and better sealing properties can be obtained with lower force.
The seat surface and seal component are disposed on the inside of the fuel filler pipe, allowing the fuel filler pipe to protect the seal surface and the like against external forces and loads. Accordingly, more consistent sealing protection is attained.
Examples of structures for the seal component include O-rings, seal rings with a flat cross section, and the like. The seat surface can be flat, and can also be in the form of an annular protrusion in linear contact with the seal component, etc. The seal component, such as a seal ring, can be housed in an annular recess sized dispose the seal ring at a location lower then the upper surface of the shutter. In this case, the seat surface can be disposed so as to protrude into the annular recess.
The connector can comprise cam unit for converting the rotational force applied by the handle into force in the direction in which the shutter closes the passage.
The cam unit can furthermore convert the rotating force of the cap main body into force for compressing the seal component between the seat surface and the shutter to provide higher sealing force. The cam unit allows a greater degree of freedom in the selection of the material, surface treatment (state), and shape of the seal component, and also allows higher sealing properties to be designed, without subjecting the seal component to frictional forces and torque as in conventional technology.
In a preferred embodiment of the cam unit, the handle is provided with an engagement protrusion insertable into an insertion hole of the shutter. Rotational operation of the handle causes the engagement protrusion to engage the shutter and maintain the passage closed. Since the engagement protrusion does not protrude from the shutter, the fuel gun can be inserted without hindrance from the engagement protrusion or the like.
A guide surface in the form of a continuous curve directed toward the seal opening can also be provided in the passage on the opening side of the seat to face where the fuel gun is inserted. When the fuel gun is inserted into the passage on the opening side during fueling, the tip of the fuel gun is guided into the seal opening by the guide surface. The fuel gun can thus be smoothly inserted into the passage on the opening side without any deformation or the like caused by collision with the side of the opening of the seal opening. The sealing properties are thus preserved, without deformation of the seal surface during fueling.
According to another embodiment of the present invention, a fueling device for fueling a fuel tank comprises a fuel filler pipe that has a fuel passage for supplying fuel to a fuel tank, and that is formed of a first resin material. A casing main body that is disposed in the fuel filler pipe for introducing fuel has an inlet passage connected to the fuel passage, and a seat surface facing the inlet passage. The casing main body is formed of a second resin material different from the first resin material. A cap main body opens and closes the inlet passage, and has a seal component seated on the seat surface so as to seal the passage against the outside. An engagement component is interposed between the fuel filler pipe and casing main body to seal the space therebetween in an air-tight manner. The engagement component is formed of a third resin material. A portion of the sealing component is unitarily formed with either the casing main body or fuel filler pipe by insert molding, and the rest of the seal component is unitarily formed with the other of the casing main body or fuel filler pipe by welding. For example, when a portion of the seal component is insert molded to the casing main body, the fuel filler pipe is welded. On the other hand, when a portion of the seal component is insert molded to the fuel filler pipe, the casing main body is welded.
In this embodiment, the cap main body for opening and closing the inlet passage of the casing main body is removed to allow fuel to be supplied through the fuel passage of the fuel filler pipe to the fuel tank. When the inlet passage is closed by the cap main body, the seal component is seated on the seat surface to seal the passage against the outside.
Both the fuel filler pipe and casing main body are formed of resin material. The fuel filler pipe is formed of a first resin material, and the casing main body is formed of a second resin material that is different from, and does not melt with, the first resin material. But the fuel filler pipe and the casing main body are unitarily connected in an air-tight manner by the seal component. That is, a portion of the seal component is united with either the casing main body or fuel filler pipe by insert molding, while the other part of the seal component is united with the other of the casing main body or fuel filler pipe by welding. That is, the seal component unites the casing main body and fuel filler pipe, which do not melt together, by means of insert molding and welding.
Since a portion of the seal component can be welded to allow the casing main body or fuel filler pipe to be united in an air-tight manner, different resin materials and forming methods can be selected to form these components as befits their separate functions. For example, a material capable of affording greater surface precision on the seat surface can be used as the second resin material for forming the casing main body, while the first resin for forming the fuel filler pipe can be selected in consideration of formability, mechanical strength, cost, and the like. Different forming methods can be selected, such as injection molding for the casing main body and blow molding for the fuel filler pipe. Examples of welding include heat welding as well as other welding methods such as ultrasonic welding.
In a preferred modification to this embodiment, ribs with enlarged surface area are used to join the seal component and casing main body or fuel filler pipe at the connecting surface so as to enhance the bonding strength of the two by insert molding.
The other of the present inventions is a fueling device for fueling a fuel tank through the fuel passage of a fuel filler pipe, comprising: a handle operable to open and close the fuel passage; a shutter, disposed in the fuel filler pipe, for opening and closing the fuel passage; and a connector that connects the handle and shutter in such a way that an operating force exerted by the handle to close the fuel passage is converted into force to close the shutter.